The present invention relates to electrical couplings and components of couplings. The invention is more particularly concerned with couplings having grounding fingers that establish electrical connection between parts.
Electrical couplings, such as those between electrical cable clamps to electrical connectors or the like, often have an outer metal shell in several parts that are retained with one another by means of a coupling ring. The coupling ring is rotatably mounted on one part of the coupling and is internally threaded, so that it can be screwed onto the cooperating other part of the coupling to draw parts into mating engagement. The metal shell of the coupling usually provides a part of a ground path for an assembly in which the coupling is connected. While there is electrical connection between the parts of the coupling via the interfacing accessory teeth on the electrical connector and cable clamp, this in many assemblies, provide only a poor electrical connection or high resistance conductivity because of sloppy engagement between interfacing accessory teeth and also compounded by the presence of contaminants such as dirt or grimes or rust or poor assembly.
The present invention provides an improved, reliable and consistent electrical continuity between an electrical connector and its cable clamp or xe2x80x9cbackshellxe2x80x9d by use of spring contact grounding fingers secured on one part of the coupling (such as by welding or solder), the fingers being arranged to make a sliding electrical contact with the other part of the coupling when the two are coupled together. The grounding fingers ensure a solid electrical continuity and maintain this continuity even if the two parts of the coupling are not fully mated.
It can be understood that the present invention also provide an improved, reliable and consistent electrical continuity between an electrical connector and its coupling part such as a bracket or panel or structure in the aircraft. The grounding fingers ensures a solid electrical continuity and maintain this continuity even if the connector mounting screws were insufficient in having the two parts of the coupling fully mated. This present invention grounding fingers is an improvement to the straight wave springs described in application Ser. No. 08/986,378.
It is an object of the present invention to provide a spring contact grounding fingers which solves the problems of the prior art.
It is another object of the present invention to provide an electrical coupling comprising: a first metal member of circular section; a second rotatable member mounted on a part of the first member, an annular recess formed around on inner surface of the second member or an outer surface of the first member; and an electrical contact member located in the annular recess, the contact member having a plurality of spring contact fingers extending axially of the coupling, the contact member being arranged to engage the outer surface of the first member and the inner surface of the second member such that the contact member makes electrical contact with at least the first member.
The contact fingers are preferably bent inwardly of the contact member. The contact member may include an annular band encircling the first member and integral with the fingers, the fingers projecting from the opposite edges of the band. The spring contact grounding may be of beryllium copper. The first member may be a first shell and the second member a coupling ring, the annular recess being formed around the inner surface of the coupling ring. The annular band of the contact member is axially installed on the first shell thus the other end of the contact member is arranged for contact with an outer surface of a second shell. The contact member may be entirely enclosed within the coupling ring.
It is a further object of the present invention to provide an electrical coupling comprising: a first metal shell of circular section; a coupling ring mounted on a part of the first shell, the coupling ring being arranged to engage a surface of a part of a second shell; an annular recess formed around an inner surface of the coupling ring; and the contact member having a plurality of spring contact fingers extending axially of the coupling and (for this description but not limited to) bent inwardly into first and second resilient U-shape portions at opposite ends, the contact member being arranged to engage the outer surface of the first shell and an outer surface of the second shell such that the contact member makes a low impedance connection between the two shells.
Yet another object of the present invention to provide an electrical coupling comprising: a first member of circular section; a second rotatable member mounted on a part of the first member; an annular recess formed around an outer surface of the first member; and an electrical contact member located in the annular recess, the contact member having a plurality of contact fingers extending axially of the coupling and bent inwardly into first and second resilient U-shaped portions at opposite ends of each finger, the fingers at both ends of the contact member engaging the recess in the first member and an outer surface of the contact member engaging the inner surface of the second member such that the contact member makes electrical and low impedance connection between the first and second members.
A still further object of the present invention to provide a contact member for making electrical and low impedance connection between different parts of a coupling assembly, the contact member comprising: a circular band of resilient metal having fingers along opposite edges of the band, the fingers being bent inwardly to form resilient U-shape portions such that the contact member can be retained in an annular recess in the coupling with the fingers along opposite edges establishing low impedance connection between different parts.
It is also an object of the present invention to provide a contact member for making electrical and low impedance connection between different parts of a coupling, the contact member comprising: a circular band of resilient metal, a plurality of contact fingers along opposite edges of the band, the fingers being bent inwardly to form resilient U-shape portions such that the contact member can be retained in an annular recess in one of the parts of the coupling with the fingers making electrical contact with the one part and with an outer surface of the contact member contacting an inner surface of the other part such that the contact member establishes a solid and consistent electrical connection between the two parts.